일본을

일본을

"일본을" means "Japan" (as the object in a sentence).

Here, '일본을' is the direct object of the verb '계획하다', indicating what the subject is planning.

저는 여름 휴가로 일본을 계획하고 있어요.

I am planning Japan for my summer vacation.

In this sentence, '일본을' is used as the direct object of '방문할', specifying the location he plans to visit.

그는 일본을 방문할 날을 손꼽아 기다리고 있어요.

He is counting down to the day he will visit Japan.

Here, '일본을' functions as a means or medium through which the action of understanding has occurred.

우리는 일본을 통해 아시아의 문화를 더 잘 이해하게 되었어요.

We came to better understand Asian culture through Japan.